JP 2008-238921A discloses a damper control device that controls a damping force of a damper interposed between a sprung member and an unsprung member of a vehicle. With a focus on a stroke velocity of the damper and upward/downward velocities of the sprung member, the damper control device realizes a skyhook damper based on a damping force switching rule according to Karnopp control. In a case where a direction of the stroke velocity of the damper is the same as a direction of the velocity of the sprung member, the damping force of the damper is increased. In a case where the direction of the stroke velocity of the damper is different from the direction of the velocity of the sprung member, the damping force of the damper is reduced.
In such a damper control device, there is a possibility that the stroke of the damper becomes so large that the ride quality decreases. Therefore, a target value obtained by multiplying the velocity of the unsprung member by a control gain is compared with a target value for skyhook control, a larger one of the target values is used as a target damping force, and the damper is caused to output the target damping force. The control gain is set to have a large value when the stroke of the damper is large or the stroke velocity of the damper is high. Also, the target value derived from the unsprung the unsprung member is set to have a roughly large value when the stroke velocity of the damper is high and a stroke amount of the damper is large. In this way, an excessive stroke of the damper is suppressed.